Preliminary Analysis of the Impact of Incubation Temperature on Sex Ratios, Emergence Rate, and Post-emergence Metabolic Rates in Nasonia vitripennis Wasps

Temperature plays an important role in the development of ectothermic organisms, yet research is limited on how it affects the physiology of jeweled parasitic wasps (Nasonia vitripennis). This species, a model organism for studying metabolic and physiological processes, offers valuable insight into how environmental factors affect ectotherms. N. vitripennis completes its life cycle in egg, larva, pupa, and adult stages. Females parasitize Sarcophaga bullata, a flesh fly species, by laying eggs in host pupae. The larvae consume the host pupa before pupating and emerging as adults. Our study investigates how different incubation temperatures impact sex ratios, emergence rates, and post-emergence metabolic rates in parasitic wasps. We hypothesize that while temperature will not significantly alter sex ratios, higher temperatures will lead to faster emergence and increased metabolic rates. We place wasps, in the pupal stage, in small containers with controlled humidity to mimic natural conditions and incubated at three temperatures (20°C,
25°C, and 30°C), with 25°C as the control. Once the pupae become fully colored, 75 females are collected for a metabolic trial. The resting metabolic rate (determined by oxygen consumption) of female wasps is measured within 24 hours of emergence. Preliminary data at 25°C (n=8) and 30°C (n=4) suggest that higher incubation temperatures have no effect on sex ratios but result in faster emergence and a higher post-emergence metabolic rate. This research aims to expand on the knowledge of how temperature influences the physiology of ectotherms, specifically parasitic wasps, which will enable further ecological studies.